ESS102H1 Lecture : Plate Tectonics
Document Summary
Isostacy - material will sink into a liquid. Planet earth: continents on average are 300m high, have mountain belts and shelf marks boundaries, oceans on average are 4m deep, mid ocean ridges are very deep (10km); volcanic island chain plateaus. If two oceanic lithospheres meet, one will dip below the other - subduction": typically a row of volcanoes sit on overriding plate - cause earthquakes, deep sea trench at subduction zone. If a continent and ocean meet, the ocean will dip below. If a continent meets a continent they collide and form mountain: convergent boundaries form curved boundary - place where we have major volcanoes. Transform plate boundaries: where two plates pass each other, one moves on way and the other moves the different way, divergent plat boundaries are parallel, transform boundaries are adjacent, balanced plate growth means boundary doesn"t shift. Some are very large, while other are small.
